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LagrangeSon678
derivative of secx derivative of secx @Mathematics
anybody can help me?
What's that supposed to mean?
tan(x)sec(x) This are all very common derivatives... your book should have a table of them somewhere... and I would suggest just memorizing all of the trig derivatives and integrals, it will come in handy when you get to trig substitution integration.
ok.. sec(x) is the same as \[\frac{1}{\cos(x)}\] So use the quotient rule to find the derivative... \[\frac{\cos(x)(0) - 1(-\sin(x))}{\cos^2(x)}\] Simplify and you get \[\frac{\sin(x)}{\cos^2(x)}\] This can be written as \[\frac{1}{\cos(x)} * \frac{\sin(x)}{\cos(x)}\] Which is sec(x)tan(x)